Salvia extracts generally come in 5x, 6x and 10x concentrations. Dramatically less material is required the more concentrated the extract is (10x is more concentrated than 5x). A single hit of extract may be more than enough at any of these concentrations.
Salvia is unscheduled in the United States meaning it is legal to possess and sell. The federal Analog Act generally requires chemicals be chemically similar to another scheduled substance to qualify . As Salvinorin is chemically very different from any scheduled substance it is unlikely to be targeted under that act. Salvia divinorum has been added to a list of controlled plants in Australia as of June, 2002.
When smoked, Salvia generally comes on very quickly. First effects are noticed between 20-60 seconds after smoking, increasing to peak effects within 1-2 minutes.
The primary effects of Salvia divinorum last between 5-15 minutes. There is then a come-down period of 20-40 minutes before returning to baseline.
Depending on dosage, the Salvia experience can vary from a subtle, just-off-baseline state to a full-blown psychedelic experience. At higher doses users report dramatic time distortion, vivid imagery, encounters with beings, travel to other places, planets or times, living years as the paint on a wall or experiencing the full life of another individual. Needless to say these can be extremely powerful experiences and should only be attempted with a sitter. While most people remain unmoving during the experience, some individuals will attempt to get up and walk around while in a completely dissociated state.
While sub-threshold effects are somewhat innocuous--leading some people to be cavalier in subsequent experiences--once full effects are achieved, many people find S. divinorum to be unpleasantly overwhelming and more scary than fun. As has been found with pharmaceutical kappa-opioid agonists, salvia is aversive for many who try it.